During Lenin's final illness in 1923–1924, Kamenev formed a leadership troika with Zinoviev and Joseph Stalin which led to Leon Trotsky's downfall.

[1] His father, an engine driver on the Moscow-Kursk railway, had been a fellow student of Ignacy Hryniewiecki, the revolutionary who killed the Tsar Alexander II.

He joined the Russian Social Democratic Labour Party (RSDLP) in 1901,[3] and was arrested in March 1902 for taking part in a student protest, and, after a few months in prison, was sent back to Tiflis under police escort.

Later in 1902, he moved to Paris, where he met Vladimir Lenin, whose adherent and close associate he became, other Marxist exiles from the Iskra group that published the newspaper, and his wife, Olga Bronstein,[2] younger sister of Leon Trotsky.

After the failure of the reunification attempt, Kamenev continued working for Proletariy and taught at the Bolshevik party school at Longjumeau near Paris.

In January 1912, Kamenev helped Lenin and Zinoviev to convince the Prague Conference of Bolshevik delegates to split from the Mensheviks and Otzovists.

Before leaving Siberia, Kamenev proposed sending a telegram thanking the Tsar's brother Mikhail for refusing the throne.

Kamenev and Central Committee members Joseph Stalin and Matvei Muranov took control of the revived Bolshevik Pravda and moved it to the Right.

[7] However, when the Bolshevik-led Military Revolutionary Committee, headed by Adolph Joffe, and the Petrograd Soviet, led by Trotsky, staged an uprising, Kamenev and Zinoviev went along.

In January 1918, Kamenev was sent to spread the revolution to Britain and France and negotiate with the countries about the potential alliance in case Germany continued its offensive against the Bolshevik regime, but after he had been in London for a week, he was arrested and deported.

Together with Zinoviev and Joseph Stalin, he formed a ruling Triumvirate (also known by its Russian name Troika) in the Communist Party, and played a key role in the marginalization of Trotsky.

The triumvirate carefully managed the intra-party debate and delegate selection process in the fall of 1923 during the run-up to the 13th Party Conference, securing a vast majority of the seats.

In the spring of 1924, while the triumvirate was criticizing the policies of Trotsky and the Left Opposition as "anti-Leninist", the tensions between the volatile Zinoviev and his close ally Kamenev on one hand, and the cautious Stalin on the other, became more pronounced and threatened to end their fragile alliance.

However, Zinoviev and Kamenev helped Stalin retain his position as General Secretary of the Central Committee at the XIIIth Party Congress in May–June 1924 during the first Lenin's Testament controversy, ensuring that the triumvirate gained more political advantage at Trotsky's expense.

At the 14th Conference of the Communist Party in April 1925, Zinoviev and Kamenev found themselves in a minority when their motion to specify that socialism could only be achieved internationally was rejected, resulting in the triumvirate of recent years breaking up.

One of Kamenev's last public acts while he was still a major figure in the soviet leadership was to read the story The Heart of a Dog, by Mikhail Bulgakov.

According to Polish historian, Marian Kamil Dziewanowski, Kamenev was denied the position of Chairman of the Council of People's Commissars of the Soviet Union on Stalin's suggestion due to his Jewish origins.

[13] With Trotsky mainly on the sidelines through a persistent illness, the Zinoviev-Kamenev-Stalin triumvirate collapsed in April 1925, although the political situation was hanging in the balance for the rest of the year.

Stalin struck an alliance with Nikolai Bukharin, a Communist Party theoretician and Pravda editor, and the Soviet prime minister Alexei Rykov.

The struggle became more open at the September 1925 meeting of the Central Committee, and came to a head at the XIVth Party Congress in December 1925, when Kamenev publicly demanded the removal of Stalin from the position of the General Secretary.

Kamenev's first marriage, which had begun to disintegrate in 1920, as a result of his reputed affair with the British sculptor Clare Sheridan, ended in divorce in 1928 when he left Olga Kameneva and married Tatiana Glebova.

[18] While Trotsky remained firm in his opposition to Stalin after his expulsion from the Party and subsequent exile, Zinoviev and Kamenev capitulated almost immediately and called on their supporters to follow suit.

They were forced to make self-flagellating speeches at the 17th Party Congress in January 1934, where Stalin paraded his erstwhile political opponents, showing them to be defeated and outwardly contrite.

The murder of Sergei Kirov on 1 December 1934 was a catalyst for what are called Stalin's Great Purges, as he initiated show trials and executions of opponents.

I have been arrested for my ties to people who are strange and disgusting to me.The men were tried in January 1935 and were forced to admit "moral complicity" in Kirov's assassination.

[19] Kamenev was charged separately in early 1935 in connection with the Kremlin Affair, in which his nephew Nikolai Rosenfeld, a Moscow thermal power engineer, was involved as a major participant.

In August 1936, after months of rehearsal in Soviet secret police prisons, Zinoviev, Kamenev and 14 others, mostly Old Bolsheviks, were put on trial again.

In 1988, during perestroika, Kamenev, Zinoviev and his co-defendants were formally rehabilitated by the Military Collegium of the Supreme Court of the Soviet Union.

His first wife, Olga, was executed on 11 September 1941, in the Medvedev forest outside Oryol, together with Christian Rakovsky, Maria Spiridonova, and 160 other prominent political prisoners.